I assume the chanting you're talking about is where it's the ceremony that the monks and Phật Tử chants together in the afternoon, chanting from the Dharma books such as Kinh A Di Đà, Kinh Hoa Nghiêm, Kinh Pháp Hoa,........etcYou learn Dharma from chanting them, then sometimes depending on the temple and monks the monk would lecture about the Dharma after the chanting is done because it's not easy for us to just learn Dharma by our self. Sometimes we might understand it but not the true deep meaning, this is where the monks steps in and help us.The chanting is actually the Dharma if you have also wondered.

And usually Chu Dai Bi is chanted really fast, because it's very powerful when you chant it.